Textile yarn carrier having crowned winding surface



July 24, 1962 c. K. DUNLAP 3,045,945

TEXTILE YARN CARRIER HAVING CROWNED WINDING SURFACE Filed Jan. 20. 1958 r IHULHL ll lll i i z! I I 12 i l l I l ..z4

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BY CHARLES K. DUNLAP A TTORNE Y6 3,045,945 TEXTILE YARN CARRIER HAVING CROWNED WINDING SURFACE Charles K. Dunlap, Hartsville, S.C., assignor to Sonoco Products Company, a corporation of South Carolina Filed Jan. 20, 1958, Ser. No. 709,994 Claims. (Cl. 242-11832) This invention relates in general to textile yarn carriers and more particularly to an improved tubular paper body structure for such a carrier arranged uniquely for handling synthetic yarns, such as nylon and Dacron, that have elastic properties which result in imposing very severe compressive stresses on a carrier when a package of these yarns is wound thereon.

The improved carrier structure of the present invention is characterized by an exterior winding surface tapering toward each end thereof from a relatively narrow, intermediate, circumferential zone; the carrier being finally shaped from a preformed tubular paper body Originally having a substantially uniform wall thickness, and the tapered form of the exterior surface resulting in a progressively reduced Wall thickness, and a consequently denser wall structure, toward each end of the paper body from the above mentioned intermediate circumferential zone which remains at its original Wall thickness and density. As a result of this arrangement, the carrier structure of the present invention can be provided with a crowned winding surface conditioned and proportioned to give or yield under the stress imposed by a compressive yarn package wound thereon so that the yarn package will act to compress the winding surface of the carrier to a substantially cylindrical form, and will remain readily handled thereon without difliculty from other deformation of the carrier structure or complications in the withdrawal 3 of yarn therefrom.

The above described function of a crowned winding surface formed in accordance with the present invention is provided by proportioning the crown of the winding surface in relation to the progressively increasing compressive stresses exerted by a wound yarn package'from the ends thereof towards its longitudinal center, because of the traversing formed of winding pattern by which such a package is built on a carrier. The traverse winding of the yarn package results in laying the individual yarn windings spirally on the carrier winding surface with the yarn winding pattern reversing as each end of the winding surface is reached, and this reversal forms end loops of the yarn windings that do not grip the Winding surface as tightly as the intermediate spiral windings because of a greater tendency to slip later-ally thereon. Consequently, these end loops are not capable of imposing as severe a compressive stress on the carrier structure as the intermediate spiral windings and the result is to cause the compressive stresses exerted by the yarn to increase progressively from the ends of the package to a maximum toward the longitudinal center thereof.

Accordingly, by tapering the winding surface towards each end in accordance with the present invention so as to provide a denser and less yielding wall structure towards the carrier ends, while leaving the Wall in its original uncompressed state adjacent its longitudinal center, a relatively yielding wall structure can be provided toward this longitudinal center that will give under the increasing compressive stresses exerted thereat .to allow compensating deformation of the exterior winding surface while leaving the carrier structure otherwise unaffected and usable in the ordinary way despite the severe compressive stresses that must be dealt with.

These and other features of the present invention are EJ545345 Patented July 24, 1962 described in further detail below in connection with the accompanying drawings, in which:

FIG. 1 is an elevation of a textile yarn carrier embodying the present invention, the general disposition of a yarn package thereon being indicated in dotted lines and the winding pattern of the inner yarn windings also being indicated fragmentarily; and

FIG. 2 is a sectional detail illustrating the manner in which the crowned winding surface for the carrier illustrated in FIG. 1 is formed according to the present invention.

The textile yarn carrier shown in FIG. 1, as indicated generally by the reference numeral it) may be of any conventional or convenient size for handling synthetic yarns. A common size for such carriers employs a length of about 4 inches and an outside diameter of the order of about 4% inches. As previously mentioned, a tubular paper body is preformed for use in forming the carrier iii of the present invention, and this tubular paper body may suitably consist of a spiral wound tube structure formed generally in accordance with the disclosure of copcnding application Serial No. 708,273, filed January 10, 1958, and issued October 3, 1961, under Patent No. 3,002,433 to the same inventor and assigned to the same assignee, so as to provide a seamless exterior surface on the carrier it Alternatively, the tubular paper body preformed might be a convolutely wound and laminated paper tube structure, or a molded paper body or the like might be used.

As illustrated in PEG. 1, the exterior surface of the carrier It) is crowned so as to have tapering portions 12 extending toward each end thereof from a relatively narrow, intermediate, circumferential zone 14 arranged centrally of the carrier winding surface. In a typical case, this intermediate circumferential zone 14 will have a width of approximately one inch, and the tapered winding surface portions 12 will result from compressing the carrier Wall from an original wall thickness of about inch to about inch at the ends of the carrier lfi the result of which, as previously mentioned, is to leave the wall structure of the carrier ill progressively less dense toward the intermediate circumferential zone 14, so that the winding surface is yieldable to a substantially cylindrical form, as indicated by dotted lines at 114, under the stress of a compressive yarn package P wound thereon for which the previously Winding pattern of the inner yarn windings is indicated at w.

FIG. 2 illustrates the formation of the carrier to in the above described manner, a reciprocable mandrel 16 being arranged for operation in relation to a fixed. mold part 13 and a likewise reciprocable mold part 26', so as to allow a tubular paper body preform (not shown) to be placed on the mandrel 16 and then have the mold parts 18 and 2% closed thereon at tapered cavities corresponding to the tapered carrier surfaces 12 desired, with the mold parts 18 and 20 being stopped short of complete closing to leave uncompressed the previously mentioned intermediate circumferential zone 14. Each of the mold parts 18 may be further formed as indicated in FIG. 2 at 1B and 20 for heating with steam or for the installation of electrical heating means so that a surface treating material applied to the tubular paper body preform may be developed during the operation of the mold parts i3 and 20 thereon. Alternatively, the surface finishing material may comprise a resin impregnant serving further to strengthen the structure of the carrier it? upon setting therein under the influence of the heated mold parts 18 and 2%.

A textile carrier =10 of the above described form also offers important advantages in handling yarns generally, beyond dealing with the problem of compressive stresses encountered in winding some yarns as noted above. For

example, a textile carrier 1 d of the general type illustrated is characteristically used in drum winding operations, and a drum wound package tends to build up to a more or less pronounced degree adjacent its ends in relation to its intermediate portion due to the crossover of the yarn windings as the winding traverse reverses at the package ends. Such buildup of the package ends enhances the possibilities for sloughing of the package during subsequent handling and introduces other difficulties that can become extremely troublesome under certain conditions or with particular yarns. The double tapered form of the textile car rier 19 provided according to the present invention, however, makes it possible to eliminate these difiiculties entirely by compensating for the end buildup with the taper and thereby obtaining a cylindrical drum wound package.

Additionally, the double taper form of the textile carrier It) has the further advantage of providing a winding surface on which the tendency of the foundation windings to roll as the traverse reverses is resisted effectively by opposing the torces tending to make the end loops roll with the holding action of a tapered winding surface and thereby allowing a firm and stable package to be wound. It should also be noted that these latter advantages may be obtained in a textile carrier it of the type and general shape described above but formed throughout its length of a relatively unyielding material, such as a suitable molded plastic.

The present invention has been described in detail above for purposes of illustration only and is not intended to be limited by this description or otherwise except as defined in the appended claims.

I claim:

1. A textile yarn carrier comprising a tubular body, said body having a relatively narrow, yieldable portion intermediate its ends and having portions on each side of said yieldable portion of progressively decreasing yieldability toward the ends of said tubular body.

2. A textile yarn carrier comprising a tubular paper body, said paper body having a relatively narrow, uncompressed, yieldable portion intermediate its ends and having portions on each side of said uncompressed yieldable portion diametrically compressed progressively toward the end of said tubular body from said uncompressed yieldable portion with corresponding progressively decreased yieldability.

3. A textile yarn carrier comprising a tubular paper body having a smooth exterior surface, said paper body having a relatively narrow uncompressed yieldable portion intermediate its ends and having portions on each side of said uncompressed yieldable portion diametrically compressed progressively and tapered toward the ends of said tubular body from said uncompressed yieldable portion with corresponding progressively decreased yieldability.

4. A textile yarn carrier comprising a tubular paper body having a cylindrical interior bore and a Wall which tapers with a progressively reduced thickness and yieldability and a corresponding progressively increased density toward each end of said body from a relatively narrow, intermediate, circumferential, yieldable Zone.

5. The method of forming a textile yarn carrier which comprises the steps of, preforming a tubular paper body with a substantially uniform wall thickness and then diametrically compressing the wall of said body progressively toward each end of said body from a relatively narrow, circumfeerntial, yieldable Zone intermediate the length thereof that is left uncompressed to progressively decrease the yieldability of said wall toward each of said ends.

References Cited in the file of this patent UNITED STATES PATENTS 1,597,761 Burt Aug. 31, 1926 1,769,928 Lindenber-g July 8, 1930 2,495,058 Dunlap Jan. 17, 1950 2,611,154 Chevrier Sept. 23, 1952 2,765,023 Fagg Oct. 2, 1956 2,892,217 Luboshez June 30, 1959 

